1
GATE CSE 2014 Set 2
Numerical
+2
-0
Three processes $$A, B$$ and $$C$$ each execute a loop of $$100$$ iterations. In each iteration of the loop, a process performs a single computation that requires $${t_c}\,\,CPU$$ milliseconds and then initiates a single $${\rm I}/O$$ operation that lasts for $${t_{io}}$$ milliseconds. It is assumed that the computer where the processes execute has sufficient number of $${\rm I}/O$$ devices and the $$OS$$ of the computer assigns different $${\rm I}/O$$ devices to each process. Also, the scheduling overhead of the $$OS$$ is negligible. The processes have the following characteristics:
Process id tc tio
A 100 ms 500 ms
B 350 ms 500 ms
C 200 ms 500 ms

The processes $$A, B,$$ and $$C$$ are started at times $$0, 5$$ and $$10$$ milliseconds respectively, in a pure time sharing system (round robin scheduling) that uses a time slice of $$50$$ milliseconds. The time in milliseconds at which process $$C$$ would complete its first $${\rm I}/O$$ operation is __________.

2
GATE CSE 2014 Set 3
Numerical
+2
-0
An operating system uses $$shortest$$ $$remaining$$ $$time$$ $$first$$ scheduling algorithm for pre-emptive scheduling of processes. Consider the following set of processes with their arrival times and $$CPU$$ burst times (in milliseconds):
Process Arrival Time Burst Time
P1 0 12
P2 2 4
P3 3 6
P4 8 5

The average waiting time (in milliseconds) of the processes is ________.

3
GATE CSE 2014 Set 1
Numerical
+2
-0
Consider the following set of processes that need to be scheduled on a single $$CPU.$$ All the times are given in milliseconds.
Process Name Arrival Time Execution Time
A 0 6
B 3 2
C 5 4
D 7 6
E 10 3

Using the $$shortest$$ $$remaining$$ $$time$$ $$first$$ scheduling algorithm, the average process turnaround time (in $$msec$$) is _______.

4
GATE CSE 2012
+2
-0.6
Consider the $$3$$ processes, $$P1,$$ $$P2$$ and $$P3$$ shown in the table.
Process Arrival Time Time Units
Required
P1 0 5
P2 1 7
P3 3 4

The completion order of the $$3$$ processes under the policies $$FCFS$$ and $$RR2$$ (round robin scheduling with $$CPU$$ quantum of $$2$$ time units) are

A
$$FCFS:P1,P2,P3\,\,\,\,RR2:P1,P2,P3$$
B
$$FCFS:P1,P3,P2\,\,\,\,RR2:P1,P3,P2$$
C
$$FCFS:P1,P2,P3\,\,\,\,RR2:P1,P3,P2$$
D
$$FCFS:P1,P3,P2\,\,\,\,RR2:P1,P2,P3$$
GATE CSE Subjects
Discrete Mathematics
Programming Languages
Theory of Computation
Operating Systems
Digital Logic
Computer Organization
Database Management System
Data Structures
Computer Networks
Algorithms
Compiler Design
Software Engineering
Web Technologies
General Aptitude
EXAM MAP
Joint Entrance Examination